The cost isn’t exactly associated with the planner. It is hung off of RelNodes
by means of metadata providers, so it is more closely associated with RelNodes
than planner. But anyway, I think what you’re asking for is how to get a
planning environment with all the costs (aka metadata) available.
I'm looking for pointers on how I could write a standalone piece of code
that interfaces with calcite to get the cost value used by the default
planner. I'm able to create an instance of CalcitePrepareImpl and execute
queries, but I don't see an obvious way to pull out the planner instance
and get
